TWI692046B - Sensors and adjusters for consumables - Google Patents

Abstract

An apparatus for use in a processing chamber is provided.  A consumable is within the processing chamber.  A scale is positioned to measure a mass of the consumable.

Description

Sensors and adjusters for consumables

This disclosure relates to the manufacture of semiconductor devices. Specifically, the disclosure relates to the manufacture of semiconductor devices in processing chambers with consumable parts.

In the manufacture of semiconductor components, it is possible to process semiconductors in processing chambers. Some processing chambers have consumable parts. For example, the etching chamber may have a consumable edge ring, which is etched over time. Other processing chambers may have consumables over which layers are deposited.

Disclosed herein are various embodiments, including a manifestation in which a device for use in a processing chamber is provided. The consumables are located in the processing chamber. The scale is set to measure the quality of the consumables.

In another manifestation, a method is provided. Measure the mass of at least one consumable in the processing chamber. Use this processing chamber. The change in quality of the at least one consumable is measured. The at least one consumable is adjusted according to the change in the measured quality of the at least one consumable.

In another form of expression, a device is provided. Provide a plasma processing chamber. A consumable is provided in the processing chamber. The piezoelectric transducer is provided to measure the mass of the consumable and serve as an actuator for moving the consumable. The controller is electrically connected to the piezoelectric transducer, wherein the controller includes at least one CPU and a computer-readable medium electrically connected to the at least one CPU. The computer-readable medium includes: A computer readable code to measure the voltage or current from the piezoelectric transducer; a computer readable code to determine from the measured voltage or current to determine the applied voltage or current; and An applied computer readable code is used to apply the determined applied voltage or current to the piezoelectric transducer, wherein the applied applied voltage or current is applied to move the consumable in the processing chamber.

These and other features will be explained in more detail with the drawings in the following embodiments.

100: plasma processing chamber

102: Plasma reactor

104: plasma processing limited chamber

106: Plasma power supply

108: matching network

110: TCP coil

112: power window

114: plasma

116: Wafer bias power supply

118: matching network

120: electrode

124: controller

130: gas source/gas supply mechanism

140: gas injector

142: pressure control valve

144: Pump

160: edge ring

164: substrate

168: Scale bar

172: Scale

204: wire

208: top surface

304: Step

308: Step

312: Step

316: Step

324: Step

328: Step

332: Step

400: etching reactor

402: C-shaped shield

404: substrate

406: gas distribution plate

408: Chuck

424: Gas source

435: Controller

448: ESC source

449: Etching chamber

450: chamber wall

460: Scale

462: Suspension

464: Processing ring

600: computer system

602: processor

604: Electronic display device

606: Main memory

608: storage device

610: Removable storage device

612: User interface device

614: Communication interface

616: Communication infrastructure

In the accompanying drawings, the disclosed invention is illustrated by way of example (and not by way of limitation), wherein similar element symbols indicate similar elements, where:

FIG. 1 schematically illustrates a cross-sectional view of an example of a plasma processing chamber, which can be used in an embodiment.

2A-C are enlarged schematic diagrams of cross sections of the edge ring, the base plate, the electrodes, the scale, and the scale bar.

FIG. 3 is a high-level flowchart of an embodiment.

4 is a cross-sectional view of a processing chamber used in another embodiment.

Figure 5 is an enlarged bottom view of the processing ring.

FIG. 6 is a high-level block diagram showing a computer system suitable for implementing a controller.

The embodiments will now be described in detail, and reference is made to the several embodiments described in the accompanying drawings. In the following description, specific details are presented to provide a thorough understanding of the present invention. However, this The disclosure content can be implemented without some or all of these specific details, and the disclosure content includes changes that can be made based on common knowledge in this technical field. Well-known processing steps and/or structures have not been described in detail so as not to unnecessarily obscure the disclosure.

To help understanding, FIG. 1 schematically illustrates a cross-sectional view of an example of a plasma processing chamber 100, which may be used in an embodiment. The plasma processing chamber 100 includes a plasma reactor 102 with a plasma processing limited chamber 104 therein. The plasma power supply 106 is adjusted by the matching network 108 to supply power to the TCP coil 110 located near the power window 112 to generate plasma 114 in the plasma processing confinement chamber 104 by providing an inductive coupling power. The TCP coil (upper power source) 110 can be used to create a uniform dispersion profile within the plasma processing confinement chamber 104. For example, the TCP coil 110 may be used to generate an annular power distribution in the plasma 114. A power window 112 is provided to isolate the TCP coil 110 from the plasma processing confinement chamber 104 while allowing energy to be transferred from the TCP coil 110 to the plasma processing confinement chamber 104. The wafer bias power source 116 adjusted by the matching network 118 provides power to the electrode 120 to set the bias voltage on the substrate 164 supported by the electrode 120.

The plasma power supply 106 and the wafer bias power supply 116 can be used to operate at a specific radio frequency, for example, 13.56 MHz, 27 MHz, 2 MHz, 60 MHz, 400 kHz, 2.54 GHz, or a combination thereof. The plasma power supply 106 and the wafer bias power supply 116 can be made to an appropriate size to supply a range of power to achieve the desired processing performance. For example, in one embodiment of the present invention, the plasma power supply 106 may supply power in the range of 50 to 5000 watts, and the wafer bias power supply 116 may supply a bias in the range of 20 to 2000 volts. In addition, the TCP coil 110 and/or the electrode 120 may be composed of two or more coils or secondary electrodes, which may be powered by a single power supply or a plurality of power supplies.

As shown in FIG. 1, the plasma processing chamber 100 further includes a gas source/gas supply mechanism 130. The gas source 130 is fluidly connected to the plasma processing confinement chamber 104 via a gas inlet (eg, gas injector 140). The gas injector 140 may be located at any advantageous position in the plasma processing confinement chamber 104, and may take any form for injecting gas. However, preferably, the gas inlet can be used to produce A "tunable" gas injection profile, which allows the individual flow of gas to be adjusted independently to multiple areas in the plasma processing confinement chamber 104. The processing gas and by-products are removed from the plasma processing confinement chamber 104 by the pressure control valve 142 and the pump 144. The pressure control valve 142 and the pump 144 are also used to maintain a specific pressure in the plasma processing confinement chamber 104 . During the process, the pressure control valve 142 can maintain a pressure of less than 1 Torr. The edge ring 160 is placed around the substrate 164. Kiyo from Lam Research Corp. of Fremont, CA can be used to implement an embodiment. In this embodiment, the scale 172 is placed under the edge ring 160. The weighing bar 168 is placed between the scale 172 and the edge ring 160. The controller 124 is controllably connected to the gas source 130, the plasma power supply 106, the wafer bias power supply 116, and the scale 172.

2A is an enlarged schematic view of a cross section of a portion of the edge ring 160, the base plate 164, the electrode 120, the scale 172, and the scale bar 168. In this embodiment, the scale 172 is a piezoelectric transformer, which is electrically connected to the controller 124 by wireless connection or at least one wire 204 connected between the scale 172 and the controller 124. In this example, to cause the edge ring to move, the controller 124 applies a voltage across the wire 204 to the scale 172. The voltage applied to the scale 172 or the charge throughout the scale 172 causes the scale 172 to apply a force to the scale bar and therefore to the edge ring 160. When the force is greater than the weight of the edge ring 160, the edge ring will move upward. When the forces are equal, the edge ring remains immobile/stopped. When used as a scale, the system is reversed. The controller 124 obtains the electrical signal from the scale 172, which is proportional to the new weight of the edge ring 160. Therefore, the piezoelectric transducer serves as both the scale 172 (weighing at least part of the edge ring 160) and the actuator (moving the at least part of the edge ring 160).

FIG. 3 is a high-level flowchart of an embodiment. The scale is used to measure the quality of consumables (step 304). In this example, the plasma processing confinement chamber 104 is used for etching. Therefore, the edge ring 160 is expendable, it is etched away and must be replaced regularly. The processing chamber is used (step 308). In this example, the etching chamber is used to etch the substrate. The change in quality of the consumable is measured (step 312). In this example, the top of the edge ring 160 is etched away. 2B is an enlarged cross-sectional view of a portion of the edge ring 160, which is after the top portion of the edge ring 160 has been etched away, leaving an uneven top surface 208. Etching away the top portion of the edge ring 160 will cause a change in the mass of the edge ring 160, which changes the force on the scale bar 168, which changes the force applied by the scale bar 168 to the scale 172. The change in force allows the scale 172 to measure the change in weight or mass of the edge ring 160.

The controller 124 uses the measured change in quality to determine whether the consumable item needs to be adjusted (step 316). If no adjustment is required, the procedure returns to the step of using the processing chamber (step 308), and the procedure is continued. If adjustment is required, the controller 124 can determine whether the consumable needs to be replaced (step 324). If the controller 124 determines that the consumable is to be replaced, the edge ring 160 is removed and a new edge ring is provided (step 328). Then, the process returns to step 304 to measure the quality of the new edge ring (step 304). When the mass of the edge ring is lower than a critical mass, the controller 124 may determine that the edge ring should be replaced. If the controller 124 determines not to replace the edge ring 160, the consumable is adjusted (step 332). In this example, the edge ring 160 is adjusted by moving the edge ring 160.

FIG. 2C is an enlarged cross-sectional view of a portion of the edge ring 160 after the portion has been adjusted. In this example, the higher voltage applied by the controller 124 via the wire 204 increases the charge on the scale 172, which is a piezoelectric transducer. The piezoelectric transducer increases the force applied to the weighing bar 168, which raises the edge ring 160. The procedure returns to the step of using the processing chamber (step 308), and the procedure is continued.

The edge ring surrounds the electrode (which may be a ceramic electrostatic chuck, ESC) and creates a specially adjusted "pocket" below, around, and extending above the wafer surface. By carefully selecting the edge ring diameter, height, step, radius and angle (among other parameters) to adjust the chamber. The edge ring is a consumable item, and is eroded and deformed by the plasma. Eventually the edge ring becomes so worn that it can no longer be adjusted properly. At this time, the processing effect of the chamber drops and exceeds the specifications, and the edge ring needs to be replaced. The replacement of the edge ring requires opening the chamber, which interrupts the customer's productivity.

This embodiment provides a system that can adjust the edge ring in-situ to compensate for its wear. The system has two parts. One part must be able to detect how much the edge ring has consumed. Another The points must be able to adjust the edge ring based on how much it has consumed. This embodiment provides a way to accomplish movement and sensing in a small unit.

In this example, piezoelectric transducers are used for both movement and sensing. Piezoelectric actuators are electrical to mechanical converters. They receive the electrical signal and convert it into very fine, very small, and very precise mechanical motion. This movement is caused by the force applied by the actuator. This design then "reverses" the actuator and receives the force and output current/voltage instead of the current/voltage and output force. The force is the weight of the edge ring, which generates a current/voltage proportional to the weight. Changes in current/voltage will be changes in weight. The change in weight will be calibrated to the edge ring wear and the system will know how much to move the edge ring based on this reading.

If the edge ring is a single piece, it will be moved vertically by two or more (possibly three or four) piezoelectric transducers. From below the edge ring, the converter will push the ring up to move it, and measure its weight change to analyze its wear.

Such a system improves the system that uses lasers and mirrors to measure the etching of the edge ring. Systems using lasers and mirrors are bulky and are not ideal for incorporation into processing chambers. Such a system is also required for the passage of laser signals into and out of the chamber. This requires additional windows and seals in sensitive locations.

The above example further improves the laser and mirror system. The above example solves the problem by saving space, requiring little vacuum guidance, and not conflicting with existing processing chamber hardware. By using existing hardware and piezoelectric actuators, the above embodiment solves several assembly, thermal, and RF signal issues for edge ring condition analysis.

A preferred embodiment uses a piezoelectric transducer that applies force to adjust the edge ring position and also senses the weight change to determine the amount of adjustment required. Another design will use a pneumatic converter. The pneumatic converter converts the pressure into a force to move the edge ring. Then, the actuator will switch to sense The weight of the edge ring changes and a pressure is output, which will tell the tool how much to adjust the position of the edge ring.

4 is a cross-sectional view of a processing chamber in another embodiment. The etching reactor 400 includes a gas distribution plate 406 and a chuck 408 that provide gas inlets, and is surrounded by chamber walls 450 in the etching chamber 449. In the etching chamber 449, the substrate 404 on which the stack is formed is placed on top of the chuck 408. The chuck 408 may provide a bias voltage from the ESC source 448 as an electrostatic chuck (ESC) for holding the substrate 404 or may use another clamping force to hold the substrate 404. The gas source 424 is connected to the etching chamber 449 via the gas distribution plate 406. The plasma confinement shield (in this embodiment, it is a C-shaped shield 402) surrounds the plasma volume. In this example, capacitive coupling is used to generate plasma. An example of such a system is Flex from Lam Research Corp. of Fremont, CA. In this example, the complex scale 460 is provided on the gas distribution plate 406. Each of the plurality of scales 460 is attached to one of the plurality of hangers 462. Each of the plurality of suspension rods is connected to the processing ring 464. In this example, the scale 460 may include a piezoelectric transducer, which is electrically connected to the controller.

FIG. 5 is an enlarged bottom view of the processing ring 464. FIG. In this example, the processing loop 464 is divided into four segments. Each section is connected to two of the plurality of suspension rods 462. In this example, the tension of the plurality of suspension rods 462 is used to measure the mass of the processing ring 464, rather than the compression force to measure the mass of the processing ring 464. In addition, the quality of each segment can be used instead of measuring the quality of the entire processing ring 464. In this embodiment, deposits may form on the processing ring 464. Therefore, in this embodiment, the adjustment of the processing ring can be performed as part of the adjustment of the consumables by performing a deposit removal step on the processing ring. In the same or another embodiment, the segments of the processing ring 464 may be raised or lowered as part of the adjustment of consumables (step 332). During such a movement, the mass of a segment may cause the segment to be raised or lowered. In another example, the quality of one segment may cause the elevation or decrease of another segment. In such an embodiment, the mass of one segment can be used to determine the required compensation for the area of the chamber around another segment.

FIG. 6 is a high-level block diagram showing a computer system 600 suitable for implementing the controller 435 used in the embodiment. Computer systems can take many physical forms, ranging from integrated circuits, printed circuit boards, small handheld devices to giant supercomputers. The computer system 600 includes one or more processors 602, which may further include an electronic display device 604 (for displaying graphics, text, and other data), main memory 606 (for example, random access memory (RAM)), storage Device 608 (eg, hard drive), removable storage device 610 (eg, optical drive), user interface device 612 (eg, keyboard, touchscreen, keypad, mouse, or other pointing device, etc.) And a communication interface 614 (for example, a wireless network interface). The communication interface 614 enables software and data to be transferred between the computer system 600 and external devices via a line. The system may also include a communication infrastructure 616 (eg, communication bus, cross-over bar, or network) connected to the aforementioned devices/modules.

The information transmitted through the communication interface 614 may be, for example, an electronic, electromagnetic, optical signal form or other signal form that can be transmitted through a communication line that can transmit signals, and is a signal form received by the communication interface 614. The aforementioned communication line may use wires Or cable, optical fiber, telephone line, mobile phone line, radio frequency line, and/or other communication channels. Using such a communication interface, one or more processors 602 can receive information from the network or output information to the network while performing the aforementioned method steps. Furthermore, the method embodiments can be completely executed by the processor, or can be executed through a network (such as the Internet) in combination with a remote processor sharing part of the processing.

The term "non-transient computer readable medium" (non-transient computer readable medium) is commonly used to refer to, for example, main memory, auxiliary memory, removable storage devices, such as storage devices such as hard drives, flash memory, etc. , Drive memory, CD-ROM and other forms of permanent memory media, and should not be used to cover temporary content, such as carrier waves or signals. Examples of computer code include, for example, machine code generated by a compiler, and files that contain higher-level codes and are executed by a computer using an interpreter. The computer-readable medium may also be a computer code transmitted by a computer data signal embodied on a carrier wave, and the computer code represents a series of instructions that can be executed by the processor.

In one embodiment, the computer readable code in the storage device 608 enables the piezoelectric transducer to be used as a scale. Such software can first measure the voltage or charge on the piezoelectric transducer. Such software then correlates the measured voltage or charge with mass. Such association can be expressed as a function or can be provided by a lookup table. The associated quality will then be provided. The computer readable code in the storage device 608 can also enable the piezoelectric transducer to act as an actuator. Such software may use the associated mass to determine the desired force, or displacement applied to the processing ring 464. The software will then find the voltage or charge associated with the desired force or displacement. The software then applies the found voltage or charge to the piezoelectric transducer.

In another embodiment, the software for scales and actuators can be further combined by using the measured voltage or charge to determine the applied voltage or charge for the desired displacement and whether it must be moved Except for consumables. Such an embodiment still has a scale and an actuator, however, a tighter combination is used, so that the mass is not calculated, but a voltage symbolizing the mass is used to determine whether actuation or replacement is needed. Using voltage or charge as a quality indicator may not determine the final quality, but use the quality indicator to determine an action, where such action is based on a change in mass, which is reflected in a change in voltage or a change in charge, and Then reflect the change in the position of consumables.

By using converters for both scales and actuators, the floor area of the equipment used to perform these two functions is reduced. In different embodiments, the change in mass can be measured after using the chamber a different number of times. For example, the quality can be measured after processing each wafer, or the quality can be measured after processing 100 wafers. In the above embodiments, the scale is provided by piezoelectric transducers and related electronic components, such as a controller and software that provides quality measurement. Without proper software, piezoelectric transducers cannot be used to measure mass, which means that such piezoelectric transducers are not scales. Such a change in voltage or charge is then used to determine the voltage or charge that should be applied for the desired actuation.

Although the present invention has been described through several preferred embodiments, there are still many substitutions, alterations, and various substitution equivalents that fall within the scope of the invention. There are many alternatives for implementing the method and device of the present invention Alternative way. Therefore, it is intended that the following appended claims be interpreted as including all such substitutions, changes, and various substitution equivalents that fall within the true spirit and scope of the present invention.

100‧‧‧ plasma processing chamber

102‧‧‧Plasma reactor

104‧‧‧Limited chamber for plasma processing

106‧‧‧ Plasma power supply

108‧‧‧ matching network

110‧‧‧TCP coil

112‧‧‧Power window

114‧‧‧Plasma

116‧‧‧wafer bias power supply

118‧‧‧ matching network

120‧‧‧electrode

124‧‧‧Controller

130‧‧‧Gas source/gas supply mechanism

140‧‧‧Gas injector

142‧‧‧pressure control valve

144‧‧‧pump

160‧‧‧edge ring

164‧‧‧substrate

168‧‧‧Scale bar

172‧‧‧Scale

Claims (13)

An apparatus used in a processing chamber, including: an edge ring in the processing chamber; and a piezoelectric transducer configured to function as a scale and as an actuator, the scale is provided to measure the The mass of the edge ring, and the actuator is used to move the edge ring according to the mass measured by the scale, wherein one of the current and voltage measured by the piezoelectric transducer is used to determine the Mass, and one of applied current and applied voltage provides movement of the actuator. The device used in the processing chamber as claimed in item 1 of the patent scope further includes: a controller electrically connected to the piezoelectric transducer. For example, the device used in the processing chamber of item 1 of the patent application scope, wherein the processing chamber is a plasma processing chamber. The device used in the processing chamber as claimed in item 1 of the patent scope, wherein the edge ring comprises a segmented ring. For example, the device used in the processing chamber of item 1 of the patent application, in which the scale further includes a physical computer-readable medium, including: a computer-readable code for measurement, for measuring the voltage from the piezoelectric transducer ; And computer-readable codes for use, to use the measured voltage as a quality indicator. For example, the device used in the processing chamber according to item 5 of the patent application scope, wherein the actuator further includes a physical computer-readable medium, including: a computer-readable code for determining, to determine the applied voltage; and The applied computer readable code is used to apply the determined applied voltage to the piezoelectric transducer. The device used in the processing chamber as claimed in item 1 of the patent scope further includes: a controller electrically connected to the piezoelectric transducer, wherein the controller includes: at least a CPU; and a computer-readable medium, electrically Connected to the at least one CPU, wherein the computer-readable medium includes: a computer-readable code for measuring to measure the voltage or current from the piezoelectric transducer; and a computer-readable code for determining to The measured voltage or current to determine an applied voltage or current; and a computer readable code for applying to apply the determined applied voltage or current to the piezoelectric transducer, wherein the determined applied voltage or current The edge ring is moved in the processing chamber. A method used in semiconductor processing, comprising: measuring the mass of at least one edge ring in a processing chamber by using a piezoelectric transducer as a scale; using the processing chamber; by using the piezoelectric The transducer acts as a scale to measure the change in mass of the at least one edge ring; and according to the measured mass change of the at least one edge ring, the at least one is adjusted by using the piezoelectric transducer as an actuator Edge ring. For example, the method used in semiconductor processing according to item 8 of the patent application scope further includes: replacing the at least one edge ring according to the change in the measured quality of the at least one edge ring. The method for use in semiconductor processing according to item 9 of the patent application scope, wherein the step of adjusting the at least one edge ring includes: moving the at least one edge ring. The method for use in semiconductor processing as claimed in item 8 of the patent scope, wherein the step of adjusting the at least one edge ring includes: adjusting the at least one edge ring according to the change in the measured quality of the at least one edge ring Vertical height. A method for use in semiconductor processing as claimed in item 8 of the patent scope, wherein the step of measuring the change in mass of the at least one edge ring includes measuring the voltage or current from the piezoelectric transducer, wherein the adjusting the at least one edge The step of the ring includes applying a voltage or current to the piezoelectric transducer, which adjusts the vertical height of the at least one edge ring. A device used in semiconductor processing, comprising: an edge ring, which is arranged in a processing chamber; a piezoelectric transducer, which is arranged to measure the mass of the edge ring and acts as an actuator to move the edge ring; A controller electrically connected to the piezoelectric transducer, wherein the controller includes: at least one CPU; and a computer-readable medium electrically connected to the at least one CPU, wherein the computer-readable medium includes: a computer used for measurement Code reading to measure the voltage or current from the piezoelectric transducer; A computer readable code for determination, to determine an applied voltage or current from the measured voltage or current; and a computer readable code for application, to apply the determined applied voltage or current to the voltage An electrical converter in which the determined applied voltage or current moves the edge ring in the processing chamber.

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